The invention relates to the application of mechanical oscillations, for example ultrasound oscillations, in situations in which limited spatial conditions limit the freedom of movement. It particularly relates to a device for deflecting mechanical oscillations, in particular to a sonotrode or a coupling piece.
Ultrasound processing apparatus are used increasingly in the medical field, amongst others, in dentistry. One example of an application of ultrasound apparatus in medicine, in particular dentistry, is a newly developed method for anchoring implants and preparations in porous tissue. The method for example is described in the documents WO 02/069,817, WO 2004/017,927 and WO 2004/017,857.
Ultrasound processing apparatus for medical use practically often have an elongate form with a handle, so that they may be used similarly to a dentist's drill in the manner of a hand tool. The, for example, piezoelectric oscillation exciter excites a sonotrode into longitudinal oscillations which transmits these to a tool or a work piece. However, on account of the elongate form of the apparatus, the work at difficultly accessible locations is made more difficult.
A sonotrode is known from EP 0 594 541, which is designed as an annular bending oscillator. The sonotrode oscillates about four node points, which renders possible a deflection of the oscillation about an angle of 90°. The sonotrode may also oscillate about more than four nodes, so that a deflection about another integer divider of 360° is possible, for example about 120°. The disadvantage with the sonotrode of EP 0 594 541 is that it takes up, relatively, much space on account of the annular construction. Moreover, only roughly half of the power coupled into the sonotrode is also coupled out into the tool or work piece. Yet another disadvantage is the fact that a deflection is only possible about angles which are an integer divider of 360°. As a further disadvantage, only small oscillation amplitudes are possible on account of the annular design.
An alternative procedure for the deflection of ultrasound is described in the U.S. Pat. No. 6,139,320. A deflection channel contains a fluid, through which the longitudinal oscillations may be diverted according to the shape of the deflection channel. Thereby, a disadvantage is the fact that energy is lost on account of a certain compressibility of the fluid, and the fluid is thereby heated.
It is accordingly an object of the invention, to provide solutions for the deflection of mechanical oscillations, which overcome the disadvantages of the ideas according to the state of the art and which in particular is suitable for the application with restricted spatial conditions.
Solutions which permit a deflection between an oscillation receiver location and an oscillation output location by roughly 100°-130° are particularly preferred, since the work at difficult to access locations is often particularly easy at these angles.